Embattled Harlem Rep. Charles Rangel — seeking re-election to a 22nd term — will become the first congressman in a generation to survive a congressional censure if he wins tomorrow’s competitive Democratic primary.

The lawmaker faces stiff challenges from state Sen. Adriano Espaillat, who if elected would be the nation’s first Dominican-born congressman; Harlemite Clyde Williams, a former aide to Presidents Obama and Bill Clinton; Joyce Johnson, a former business and government executive; and ex-Rangel aide Craig Schley.

In 1983, two congressmen were censured for inappropriate relations with young House staffers.

Political insiders expressed surprise that Rangel, 82, who has struggled with health ailments, was running in a new district with a majority Hispanic population. They see it as his attempt to salvage his legacy after the House rebuked him in December 2010 for 11 ethics violations.

Rangel was found guilty of soliciting donations on congressional stationery for a center at City College, failing to pay taxes on his Dominican Republic villa and maintaining a rent-stabilized apartment as a campaign office.

He said his decision to run has nothing to do with the censure.

“I’m moving forward,” Rangel told The Post in an interview.

“I don’t want to be a spectator. I don’t want to be on the sidelines. If I was just a spectator next year, I’d be kicking myself.”

Even rivals admit Rangel has had a distinguished career as a liberal lion and one of Congress’ most prominent black voices.

But in a recent debate, Espaillat said Rangel’s ethics scandal damaged the Democratic Party.

“We lost over 60 seats across the country, and we lost the majority,” Espaillat said on NY1. “That was a real concern back then, and it’s a real concern now.”

Rangel’s health has also raised concerns. He lost weight and uses a cane after a spinal infection, but he says he’s on the mend.

While acknowledging Rangel’s achievements, Espaillat said it was time for him to step aside.

“When Rangel was elected, a man landed on the moon, the Mets won the World Series, and Nixon was president,” he said.

Rangel’s not ready to hang it up.

“The other people in the race don’t have the record and experience I do. I do believe I’m more qualified,” Rangel said.